The ultimate objective of the proposed investigations is to determine the influence of various dietary factors on carbohydrates and lipid metabolism and on the mechanism responsible for the observed effects. The rat and chicken, 2 animal models that differ significantly in certain aspects of gluconeogenesis, glycolysis and fatty acid synthesis, will be utilized in these studies. Specifically, the proposed investigations will consider the influence of dietary fat, protein and carbohydrate on glucose metabolism in the chicken. In vivo estimates of glucose utilization, the source of carbons and reducing equivalents for glucose synthesis in chicken liver and the activities of gluconeogenic (in particular phosphoenolpyruvate carboxykinase) and glucose phosphorylating enzymes in chicken liver will be determined. The influence of dietary ingredients which enter the glycolytic-fatty acid synthesizing pathways at the level of the hexoses, trioses and acetyl CoA on glycolytic and lipogenic activities and on rates of fatty acid synthesis in rat and chicken liver and rat adipose tissue will be determined. The effects of dietary saturated and unsaturated fatty acids on fatty acid synthesis will also be ascertained. The results of the proposed investigations should increase our knowledge of the interaction between diet, carbohydrate and lipid metabolism and should contribute to the understanding of the significance of these factors in disease states such as obesity and cardiovascular disease and in the maintenance of normal glucose homeostasis.